Help me confirm my power converter went bad

[xpauliber]

I have a 2016 Springdale 2720BH. I went camping over the weekend, all fine and good. Packed up camp, pulled the slide in, retracted the awning, lifted the stabilizers and hooked up to my truck. Everything worked exactly as it should. I unplugged the shore line from the post, threw the last few items in the truck and headed to the dump station. Started emptying out and wanted to flush the remaining water in the fresh tank down the toilet to help flush it out. I pressed down the flush pedal and nothing happened, I didn't hear the pump running. I thought it was because I was hooked up to the truck's 7-pin so I unplugged the cord, back into the bathroom but still nothing. There was a line at the dump station so I finished up and moved along.



I got home and anything related to 12V wasn't working, no lights, no water pump, no awning, no slide, no stabilizers. The electric jack worked but it's a separate direct connection to the positive on the battery.


I plugged the shore line in and my receptacles and A/C unit work but nothing 12V. I checked all the breakers & fuses in the panel and none were tripped. I pulled the power converter out and it was as hot as a firecracker and the fan wasn't working which was a red flag to me.



I specifically joined this forum to investigate this issue and after reading the various threads on similar electrical issues, here's what testing I've conducted so far:


There are two 12V breakers screwed to the front of the trailer. I tested all 4 posts and got a reading of 12.7v on each of them so I'm assuming their not tripped.


All breakers in the electrical panel weren't tripped. I have two 40 amp fuses and a bunch of 15 amp fuses in the panel and I pulled each of those but they weren't tripped.


I disconnected the battery and tested it and it was fine.



I read about how you can test the power converter by disconnecting the battery, plugging in the shore line and then putting the tester on the positive/negative leads which I did and it gave me a reading of 0.3 I'm assuming this means the converter is bad but is there a test I can do directly on the converter itself to confirm?


Another weird thing was after I did this testing, I went to hook the battery back up and I put the positive on and tightened it then went to hook the negative on and it sparked enough that it made me jump back and stop connecting it. I tried it again and same thing. My leads are clearly marked so I know I don't have them hooked up backwards. If the converter goes bad, is there a possibility that it can short out inside and have a constant draw on the battery?? With the positive side hooked up, I put my tester on the negative post and the negative lead and got a reading of 12.7v so something has a constant draw I'm assuming.


Any assistance or insight that you can provide is greatly appreciated. Thank you.

[JRTJH]

I'd guess that your power center is a 30 amp WFCO brand with a built in converter???

If so, the converter is replaceable, removeable and "testable"...

There are 5 wires on the converter. A 12VDC+, a 12VDC-, a GROUND, and two 120VAC wires.

You can read the literature on the converter here: https://wfcoelectronics.com/product/wf-8955mba/

Essentially, you can loosen the two 12VDC lugs on the fuse panel and remove them. They are the two +/- wires on the converter. Test the output with nothing connected to the converter and you should get 13.6VDC. If you do, there's something shorted/grounded or disconnected in your 12 volt system. It may be a ground lug on the chassis, it may be a shorted component inside the trailer or it may be something else...

I'd suggest your first step given your description, would be to disconnect the converter and see if you have 12 volts on the two power leads. If not, it's the converter, if you do have 12 VDC, it's the trailer system.

[xpauliber]

Thanks JRTJH! You provided much of the information that I read about earlier today and I was hoping you would reply to my message.

Here’s the unit I have.

https://photos.app.goo.gl/Hfc9kgizXNshrcwg8

https://photos.app.goo.gl/EYnwp9gn3obX4hqj8

https://photos.app.goo.gl/FHsMiYbvvzpPdrus8

[JRTJH]

That's a WFCO 8955 power center. First, remember that you're working in close proximity to exposed 120VAC terminals and they can be deadly, so use caution and maintain awareness of what you're doing and where you're working.

Before you do anything else, MAKE ABSOLUTELY SURE THAT THE TWO 40 AMP FUSES ARE GOOD (check with an ohmmeter) AND RESEAT THEM "FIRMLY" IN THEIR SOCKETS.... If things are still the same (not working):

On the right side of the converter (silver thing on the bottom) you'll find a black and a red wire. They go up to the DC fuse panel where they're connected to lugs. Loosen the lugs (make sure you know which lug the wires reconnect to). With those wires disconnected and exposed, power up the trailer or power up the converter (if it's already removed from the power center). You should have 13.6 VDC across the red/black wires.

If you do, then your problem is in the trailer wiring/battery system.
If you don't, then the problem is the converter and it needs to be replaced.

WFCO has a 2 year warranty on their products, your trailer is older than the warranty, but confirm that it's the OEM converter. (It looks to me like it's the OEM converter), but if it's a replacement and it's less than 2 years old, I'd urge you to contact WFCO's customer service department. They've been really good at sending replacement converters or power centers to customers who prefer to do their own work and don't want to take the trailer to the dealer. WFCO is quick to respond and they seem to know what they're talking about when you call for tech support.

[xpauliber]

Excellent. Thank you so much.

I will report back with my findings for future owners as well.

[xpauliber]

So I tested the converter the way you described above. I was 99% sure that the converter was going to be the problem. I tested it and got a reading of 13.88. WHAT???? So as you mentioned, the converter should be fine and the problem has to be between the battery and the converter.

I go back up to the battery. Here is what the positive lead goes to on the front of my trailer:



The positive lead from the battery attaches from the left and goes to the breaker circled in green. A ton of items connect there including a main lead that jumps over to the breaker circled in yellow which only has one wire coming off of it that goes into the frame of the trailer. I figured that was the lead that ended up back at the converter so I decided to unhook that lead going into the trailer to see if I could reconnect the battery without sparking. Bingo. I was able to connect the negative to the battery and all of those wires that connect to the green breaker must go out to my stabilizers, awning, and slide because they all started working again. No DC power inside my trailer though. I test the connection from the green breaker to the yellow breaker and have power throughout. The yellow breaker is fine as I have power on both sides of the breaker so the problem has been isolated to that large red wire going into the frame here and terminating at the converter.

I go back to the converter and decide to test the system by eliminating that red wire all together. I unhooked the red wire from the power center:

I then took my battery back to the power center and ran two jumpers from the battery to the connections on the power center where that red wire connected as well as the black ground wire and the lights in my RV turned on.

So, it seems I have a short in that main red wire that runs from the power center to the positive on the battery. I looked where that wire ran from the power center and it went immediately into the floor as you can see here:



I am completely baffled at how that thick cable which is secured on each end and immovable just shorted out all of the sudden after I packed up camp. The ONLY thing that I can think of is that it may be routed somewhere near where the slide could come in contact with it since no other moving parts are anywhere near it and when I packed up camp and brought the slide in, it somehow contacted it and shorted it out? Otherwise, it is a straight unbroken wire near no other moving parts from the entrance at the front of the trailer to the power center in the rear.

Just for final confirmation that if I replaced that red wire, my problem would be resolved, I ran a new wire from the power center where the red wire connected to the outside of the trailer and connected it to the post where that same red wire connected on the yellow breaker and bingo again, the DC power was restored so I'm 100% positive that that main red positive wire is somehow shorted.

Now the big question is what do I do to replace it since I really don't want to tear half of the rig apart to replace that wire. I have the Arctic package so the whole underbelly is insulated and enclosed so I can't see anything on the underneath.

[JRTJH]

You can, for the "short term" run a 1/2" PVC conduit along the frame rail. Attach it to the black iron gas pipe that's already there with zip ties. Run the new wire through that conduit. You'll need to route the new wire through the floor and out the edge of the coroplast and then seal those holes. Be sure that you use a wire size equal to the OEM. You're dealing with DC and the amperage load/voltage drop is critical when the battery is on one end of the trailer and the converter is on the other....

Once the new wire is run and you know the repair is functional, tape both ends of the old wire so they won't short out if they "migrate to a connector" and just leave it in place...

Then, if/when you ever find the need to pull the coroplast for some other maintenance, cut the zip ties, pull the wire out of the conduit and route it above the coroplast in the "belly"....

Electrically, the new wire will be safer inside the conduit than it was/is eposed in the belly.

[xpauliber]

Thanks for that great idea!

Have you ever heard of this problem before? Any idea, why a 2 gauge wire (or whatever size it is) would randomly short out?

[JRTJH]

I've seen some shorted wires, sometimes years after a trailer was built and a staple "shot at the factory" finally worked its way to the conductor inside the insulation. Sometimes things will vibrate loose, then they lay there, getting bent and pulled, sometimes for a year or more, then finally, the "perfect storm" occurs and the slide happens to pinch the wire and short it out. Then, maybe it's a screw holding down the floor that pierced the insulation and finally worked its way to the actual conductor inside the wire... ???

Just for curiosity's sake, did you use an ohmmeter to verify that the red wire is actually shorted ??? All you'd need to do is put one lead on the red wire and the other lead to ground... I'd do that on both ends of the red wire. Obviously, if one end is shorted, the other "should be" but if the wire is broken or cut all the way through and hung up on the slide ram, it may only show as shorted to ground on one end... That would tell you which end is shorted and also explain why the mini-breakers on the trailer bulkhead behind the battery weren't blowing or why the converter wasn't "maxed out and whining"....

At any rate, you've got the problem solved, so it seems, now just to put things back together.... Congratulations on working through it and getting to the repair and cleanup stage !!!!!

[xpauliber]

I did not test the red wire but that's a good idea and I will.

The only other thing I thought that COULD be a problem was that the red wire was first connected to some appliance or other device before it reached the converter and the short may be located there. I'm going to call Keystone tomorrow and ask their tech to review the schematic to see if that wire connects anywhere else along the way or if it indeed is a straight shot to the converter.

Thanks and I couldn't have solved this without your help John!!

[JRTJH]

You did the work, I'm just a "cheerleader" at this ball game ROFL.... It's a good feeling to have things come together. Congratulations.

[Steveo57]

The converter has short circuit protection. That might explain why it tests okay but when hooked up it doesn't power anything.

It's certainly possible that the wire from the converter to the battery could be shorted. If you ever take a look in the underbelly you'll see the mess that's in there and the wire could easily be getting crushed somehow.

[B-O-B'03]

It seems to me that if the battery is charged and the red wire has any kind of connection to ground... it would have melted or at the very least blown one or both of the circuit breakers?

Attaching the battery, to the trailer wiring, while the converter is powered on can/will make sparks if the battery voltage is below full?

Just a couple of thoughts.

-Brian

[flybouy]

I would have to agree with Brian above.
In your post #6 the first picture with picture with the green circle. With the battery cables disconnected from the battery, and the red wire in the power center disconnected: Set your VOM to ohms (resistance) and place one lead on the ground stud (where the white wire is bolted to the frame) and the other lead to the disconnected red wire. It should read infinity (no reading or "out of range" depending upon meter). If you get a very low reading like zero or single digits that's low resistance or short to ground.

This sounds like a battery disconnect that was inadvertently turned off or the reverse polarity fuses. Check fuses with VOM and not just visually.

Years ago when I was first rving, on the first trip of the season similar experience. The trailer was an ultralight and had a small slide that only extended about 18". Parked, unhitched (plugged into truck) and all was well. Went to break camp and removed shore power and slide wouldn't work. I thought the slide motor failed, after all it went out when we set up.So found the manual crank and cranked in the slide.

Go to raise the tongue jack and it didn't work. Stop, scratch head, cursed, then like Clark Griswald's wife when she flipped the light switch it hit me. Removed the battery cover and I had not connected the neg cable to the battery. The truck was connected (and running) when I set up, then the shore power supplied the dc voltage until I unplugged from the pedestal and the truck 7way was not connected. Lesson learned, installed battery disconnect swith in the the battery cover after that.

[xpauliber]

Thanks Brian but I'm not sure if I'm following. So what do you think the issue was/is?

[xpauliber]

Thanks Marshall. I will try testing like you describe. I still am not sure that it's a battery issue as I don't have a cut off switch and I've already tested the reverse polarity fuses with my meter and they were good.

[xpauliber]

I tested both ends of the red wire and both read near 0 on the ohm setting confirming what I thought was a short.

I bet the breaker that i circled in yellow above is an auto reset breaker and when the battery was hooked up while I was hauling the camper home, it probably kept tripping every time it reset. It only began sparking once I had disconnected the battery to do some testing. My thoughts anyway. At least I know the issue and will fix it this weekend.

Thanks again for all of the input.

[flybouy]

Originally Posted by xpauliber

I tested both ends of the red wire and both read near 0 on the ohm setting confirming what I thought was a short.

I bet the breaker that i circled in yellow above is an auto reset breaker and when the battery was hooked up while I was hauling the camper home, it probably kept tripping every time it reset. It only began sparking once I had disconnected the battery to do some testing. My thoughts anyway. At least I know the issue and will fix it this weekend.

Thanks again for all of the input.

If you tested "both ends" individually to ground (not end to end of the cable) than yes it's grounded. You only needed to test one end, if it's grounded it will be at either end. Most logical conclusion is the mini breaker was doing it's job. For the cost of the mini breaker I would replace it as it may be weakened from the repetitive heat cycles.

[xpauliber]

Originally Posted by flybouy

If you tested "both ends" individually to ground (not end to end of the cable) than yes it's grounded. You only needed to test one end, if it's grounded it will be at either end. Most logical conclusion is the mini breaker was doing it's job. For the cost of the mini breaker I would replace it as it may be weakened from the repetitive heat cycles.

Great idea. Will replace as well as keep one in stock in my repair box.

[Tcarter]

Check your ground fault plug. If trip no dc power.